Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the special fuel tank in your car, which uses a different kind of fuel like natural gas or hydrogen, is empty.
The vehicle's computer system has detected that the alternative fuel tank is empty.
The P2BB2 code is triggered when the Engine Control Module (ECM) receives a signal indicating that the alternative fuel tank is empty. This could be due to a sensor reading or a communication issue between the fuel level sensor and the ECM.
• Check Engine Light (CEL) is on
• Vehicle may not switch to alternative fuel
• Possible reduction in fuel efficiency
• Alternative fuel tank is genuinely empty
• Faulty fuel level sensor
• Wiring or connection issues in the fuel level sensor circuit
ECM: Engine Control Module
CEL: Check Engine Light
• Verify the alternative fuel tank is indeed empty
• Inspect the fuel level sensor for damage or malfunction
• Check wiring and connections for continuity and proper connection
• Refill the alternative fuel tank
• Replace the faulty fuel level sensor
• Repair or replace damaged wiring or connectors
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Toyota Prius
• Honda Clarity
• Chevrolet Volt
• Regularly check and refill the alternative fuel tank
• Perform routine maintenance on fuel system components
• Ensure proper storage conditions for alternative fuels
Fuel System Issue
• Refill the alternative fuel tank regularly
• Monitor fuel levels to avoid running out
• Schedule regular maintenance checks
Check with your vehicle manufacturer for warranty coverage on fuel system components.
This code is relatively uncommon and typically occurs in vehicles equipped with alternative fuel systems.
Moderate – Addressing this issue is important to maintain vehicle efficiency and performance.
Operating a vehicle with an empty alternative fuel tank may not be compliant with emissions regulations.
• Vehicle ignition in the ON position
• Alternative fuel system activated
The alternative fuel tank is usually located in the rear of the vehicle, near or integrated with the main fuel tank.
Q: Can I drive with the P2BB2 code?
A: Yes, but your vehicle may not perform optimally, and you should refill the alternative fuel tank as soon as possible.
Q: Will this code affect my vehicle's emissions?
A: Yes, running out of alternative fuel may impact emissions performance and compliance.
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